Metal forming lubricant

ABSTRACT

a. A water-soluble surface-active agent selected from semihydrogenated beef tallow potash soap, oleic acid potash soap, oleic acid soda soap, polyoxyethylene lauryl ether, polyoxyethylene sorbitan monooleate, sorbitan trioleate, lauryl amino acetate, and stearyl amino acetate; B. A water-soluble synthetic resin which is a combination of an oil-modified alkyd resin with a phenol or cresol-novolac-type resin.

United States Patent Katono et a1.

METAL FORMING LUBRICANT Inventors: Toru Katono; Yoshio Hachisu, both ofYokohama; Ryozi Saito, Tokyo; Kazushi Goto, Hiroshima; Haruo Kubotera;Kenzi Araki, both of Yokohama, all of Japan Assignee: Nippon KokanKabushiki Kaisha,

Ootemachi, Japan Filed: June 12, 1974 Appl. No.: 478,820

I Related U.S. Application Data Continuation of Ser. No. 132,151, April7, 1971, abandoned, which is a continuation-in-part of Ser. No. 777,742,Nov. 21, 1968, abandoned.

Foreign Application Priority Data Nov. 22, 1967 Japan 42-7462 Oct. 23,1968 Japan 43-76804 Nov. 13, 1968 Japan 43-82519 U.S. Cl. 252/12;252/34.7; 252/41;

252/49.5 Int. Cl..... Cl0m 7/30; C10m 7/20; ClOm 7/16 Field of Search252/12, 12.2, 12.4, 12.6,

[ Oct. 28, 1975 Primary Examiner--Delbert E. Gantz Assistant Examiner1.Vaughn Attorney, Agent, or FirmMichae1 S. Striker [5 7] ABSTRACT a. Awater-soluble surface-active agent selected from semi-hydrogenated beeftallow potash soap, oleic acid potash soap, o1eic acid soda soap,polyoxyethylene lauryl ether, polyoxyethylene sorbitan monooleate,sorbitan trioleate, lauryl amino acetate, and stearyl amino acetate;

b. A water-soluble synthetic resin which is a combination of anoil-modified alkyd resin with a phenol or cresol-novolac-type resin.

1 Claim, 5 Drawing Figures US. Patent T Oct. 28, 1975 Sheet 1 of33,915,869

ii; i; f

OUTER DIAMETER AFTER BREAKAGE 0 lo 20 3O 4O 50 WATER SOLUBLE SYNTHETICRESIN (HlTANOL 6080 N) o- WATER SOLUBLE SURFACE ACTIVE AGENT 50(DICE-LEX SOAP) TEST SHEET: sPc-s 480mm (BANKED DIAMETER) x 0.8mm(THICKNESS) LUBRICANT: DIE SIDE LUBRICATING STAMPING couomou: PUNCHDIAMETER ZOOmrnfl,

uucume SPEED lBm/min RATIO OF 23 LIMIT DRAWING 0 5 IO I5 20 COATINGAMOUNT (Q/m US. Patent Oct. 28, 1975 Sheet 2 of 3 OUTER DIAMETER AFTERBREAKAGE STAMPING OIL B (SUPERIOR) STAMPING OIL A SOLD DRY LUBRICANTFILM B SOLD DRY LUBRICANT FILM A THE INVENTED ONE TEST SHEET: SPC-3480mmflBLANKED DIAMETER) X 0.8 mm (THICKNESS) LUBRICANT: DIE SIDELUBRICATING STAMPING CONDITION: PUNCH DIAMETER 200 mm 5 PUNCHING SPEEDIBm/min IT I 5 THE RESIDUAL MOISTURE (96) U.S. Patent Oct. 28, 1975Sheet 3 f 3 80 Drymg condmon: Room Temperature C Humidity vThe InventedOne 60- Residuol moisture (7Q) min. min. min. min. hr.

METAL FORMING LUBRICANT This is a continuation of application Ser. No.132,151, filed on Apr. 7, 1971, which application Ser. No. 132, 151 inturn is a continuation-in-part of Serial No. 777,742 filed on Nov. 21,1968, both now abandoned, by the same inventors in respect of DRY LU-BRICANT AND METHOD OF MANUFACTURING METALS COATED THEREWITH.

BACKGROUND OF THE I INVENTION The invention relates to a lubricant forcoating steel, particularly steel sheets, to prepare the steel forforming operations, particularly deep-drawing.

Deep-drawing of steel sheets is particularly used for making automobileparts, electrical home appliance parts and metal pipes. It is also usedon steel for drawing to form metal wires, particularly electric wires.

The lubricant for these purposes must form a film on the metal and mustmeet a number of requirements.

a. It must have high power lubricating properties.

b. It must be adapted to be readily removed from the metal afterforming.

c. It must have good anti-corrosion properties.

d. It must be useful for dry forming of the steel parts.

e. It must have a high resistance against sticking to the differentparts involved.

f. It must be well adapted for welding, including spot welding.

g. It must be non-toxic, non-odorous, and noninflammable.

Present day lubricants meet some of these objectives, but cannot meetthem all.

Particularly steel sheets coated with conventional lubricants are hardto dry and require extensive periods for the drying operation. Theyoften are not useful for high-speed stampor punch-forming of metals, andif used for these purposes require undue apparatus and processes to beemployed.

The present invention, accordingly, has the object to provide for alubricant for these purposes which will meet all of these requirementsand still be easily applicable to the steel, in particular to steelsheets for deep drawing operations.

SUMMARY OF THE INVENTION These objects are met by a lubricant whichcomprises a mixture of a surface-active agent and a water-solublesynthetic resin in relative amounts between 20 and 80 parts ofsurface-active agent and between 80 and 20 parts of water-soluble resin.Preferably, the lubricant includes 1 to 50 parts of a water-soluble orwater-emulsifiable lubricating oil for each 100 parts of the mixture ofsurface-active agent and water-soluble resin.

The steel is coated with the lubricant after preheating to between 80and 100C and subsequent drying so as to reduce its moisture content tobelow 10% by weight. The coating is thereafter applied to the steel.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and is method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING 5 the lubricant of the invention andthe outer diameter of a test piece after breakage in flat bottomdeep-drawing;

FIG. 2 is a comparative diagram showing on one hand a conventionallubricant, and on the other hand the lubricant of the present invention;

FIG. 3 is a similar comparative diagram showing the drying speed of thelubricant of the invention compared with the drying speed of soap;

FIG. 4 is a diagram illustrating the relationship between the amount oflubricant coated on the steel and the limit of drawing ratio(LDR)(maximum drawing ratio);

FIG. 5 is a diagram illustrating the relationship bewteen the residualmoisture on the steel and the limit of drawing ratio (LDR) in a steelcoated with the lubricant of the invention.

DETAILED DESCRIPTION OF THE INVENTION AND OF PREFERRED EMBODIMENTS Aswill be further explained below, the lubricant of the invention issuitable for stamping speeds in excess of 20 m/min. Conventional drylubricants used for this purpose fail at speeds exceeding 10 m/min.They'are only good for rates up to mm/min. Actually, the properties ofthe lubricant of the invention do improve with higher stamping speeds.The lubricant of the invention, as will be further explained, issuitable for stamping speeds even in excess of 20 m/min.

A wide range of water-soluble surface-active agents may be used in thelubricants of the invention. Reference is made to the comparative testswith different lubricants illustrated in Table 6 below. A broad list ofsuitable surface-active agents includes the following:

1. Anionic water-soluble surface-active agents: aliphatic acid salts incarboxylic acid soap of the formula RCOONa(K,NI-I wherein R: C CExamples are alkali metal soaps of saturated or unsaturated aliphaticacids, for example oleic acid soda soap, oleic acid potash soap, castoroil soap, beef tallow soda soap, soyabean oil soap.

2. Cationic agents:

aliphatic amine salts:

wherein X is an acid, and R R and R are H or alkyl from C to C Anexample is acetamine (lauryl amine acetate, C H NH -CH COOH, [Acetamine24 made by Kao Soap Company] or stearyl amine acetate [Acetamine 86 madeby the same company]).

3. Nonionic agents:

1. polyoxyethylene alkyl ethers RO(C I-l O),,I-I, for examplepolyoxyethylene-oleyl ether (Emulgen 430 of the Kao Soap Company [C HO(C 4 2. polyoxyethylene sorbitan alkylesters (for example Emasol 4130of the same company, a polyoxyethylene sorbitan monooleate) 3. sorbitanalkyl esters, for example Emazol 430, which is sorbitan trioleate(aromatic group), made by the same company.

Preferred anionic water-soluble surface-active agents are saturatedaliphatic acid salts having 8 to 22 carbon atoms. An example is amixture of capric acid (C H 'COOH), lauric acid (C l-I COOH), myristicacid (C, H -,-COOH), palmitic acid (C H COOH), stearic acid (C H COOH),and a mixture of unsaturated aliphatic acids having 8 to 22 carbonatoms, oleic acid [CH (CH CH=CH(CH COOH], linolic acid [CH (CH CH=CHCHCl-l=Cl-l(Cl-l COOl-l], linolenic acid [CH (CH )Cl-l=Cl- (Cl-I)Cl-l=CH(Cl-l )CH=CH(CH COOH], and ricinoleic acid [Cl-l (Cl-lCl-l(OH)CH CH=CH(CH COOH].

The water-soluble synthetic resins may be the following:

1. Resins which generally come under the term phenolic resins such ascresol-modified novolac-type resms;

2. alkyd resins such as linseed oil, coconut oil, or castor oil modifiedalkyd resins;

3. phenolic-alkyd resin combinations such as linseed oil-modified alkydresins which are combined (further modified) with a cresol or phenolnovolac resin.

The resins must be water-soluble and should also be soluble incombination with the surface-active agent and the water-soluble oil.

As has been indicated, preferably a third component is included in thecombination. This is a water-soluble or water-emulsifiable oil, by whichterm is understood an oil which is dispersed in water by emulsification.

The amounts of the three components are as follows: The mixture betweensurface-active agent and watersoluble synthetic resin should comprise to80 parts of the surface active agent and 80 to 20 parts of thewater-soluble resin.

To 100 parts of this mixture, if desired, there may then be added 1 to50 parts of the water-soluble oil. All parts to be understood by weight.

If the water-soluble surface-active agent is present in excess of 80%,and a corresponding reduction of the water-soluble resin is effected,the results regarding adhesion to the steel sheet are generally poor.Conversely, if the water-soluble resin exceeds 80 parts, and thesurface-active agent is present in correspondingly lower amounts, theresultant mixture becomes too sticky and the resistance to sticking andblocking is decreased.

If the amount of the water-soluble oil is below 1 part, the oil wouldhave no appreciable effect. On the other hand, if the oil exceeds 50parts of the mixture of the mixture of surface-active agent and resin,it will be difficult to obtain uniformity of the composition because ofcoagulation.

The optimum ratios of amounts are about as follows:

water-soluble surface-active agent 30-70 parts water-soluble syntheticresin 7030 parts water-soluble oil 5-40 parts The lubricant is appliedin an aqueous solution of a water content of between 5 and 60% byweight. Again, if the amount of water is too small, the solution becomessticky and no uniform coating will be obtained. On the other hand, iftoo much water is added, the dry- 4 ing is too slow and a film ofsuitable thickness is hard to obtain.

In general, inclusion of the oil as a third component is definitelypreferred because of the increased lubrication and the resultingimprovement of the forming and drawing operation.

In applying the lubricant of the invention at a ratio, for instance, of10 g/m it was found that if the moisture content was to be reduced below5%, as is desirable in some cases, it was necessary to apply a hot-airblast of a temperature of 150C at a speed of application of 5 m/sec fora period of 35 seconds in case of a sheet of 0.8 mm thickness. If thesheet had a thickness of 3.2 mm, the application of the hot-air blastwas for 60 seconds. Accordingly, if the conveyor moved, for example, ata speed of 60 m/min, a drying zone of more than 60 m in length would berequired on which length no guiding roll should be provided. Thisobviously would result in difficulties with the apparatus. Besides, moredifficulties would occur with respect to the tracking of the sheet. Thecost of equipment, in any case, would be excessively high.

To eliminate these objections it was found that the temperature of thehot-air blast should be increased. With a temperature of the hot-airblast above 200C, however, bubbles were generated on the lubricantcoatedsurface. This reduced the commercial grade of the coated steel, and alsohad an adverse physcial and chemical effect on the properties of thelubricating film. All this applies for sheets as well as for metaltubing and wire.

The lubricant of the present invention is slow-drying. FIG. 3illustrates a comparison of the lubricant of the invention with awater-soluble surface-active agent used alone in the form of a soap. Ascan be seen, the lubricant of the invention retains approximately 40% ofthe original moisture after a period of 90 minutes. Thereafter, andduring a period of about 16 hours, it still retains 35% of the originalmoisture. Soap alone retains only 15% after 30 minutes and approximately2% after a period of 60 minutes.

Preferably the coating of the present invention is applied in an amountof 3 to 20 g/m Most preferably the amount is between 10 and 20 g/m Theresidual moisture is thus dried to an amount of less than 10% of theinitial moisture, and preferably to an amount below 5%.

The reduction of the moisture is best obtained by rapid drying with ahot-air blast. The physical and chemical properties of the lubricant arethereby preserved at their maximum value while the moisture is reduced.

The coating is effected by subjecting the metal sheet, metal strip orwire to a preceding cleansing with a degreasing solution and then to aheat treatment at a temperature of -l00C. The preheating treatment maybe effected by a high-pressure steam blast on the order of 2 to 15 kg/cmdirected against the surface of the steel sheet or, alternatively, thesheet may be immersed in hot water at a temperature above C.

Table 1 illustrates the heating times required to heat a steel sheet upto C for various thicknesses and various methodsof applying heat.

TABLE 1 Time for heating steel sheet to 100C by different heatingmethods.

With the high-pressure steam heat, the necessary temperature increasecan be obtained with a simple and inexpensive apparatus, provided thatsteam of sufficiently high pressure is used.

The immersion in hot water at a temperature of 100C requires somewhatlonger times and the introduction into a furnace requires a rather longtime. By infrared radium lamp, the time of application is ratherexcessive.

After completion of the cleansing and preheating step the lubricant isapplied by coating. This may be done by air spray or by other methodssuch as rollers or immersion.

The viscosity of the lubricant should be such as to permit applicationwithin -45 seconds with a Ford Cup No. 4, depending on the amount oflubricant applied and the speed of the conveyor belt.

For application the lubricant should be at a temperature between roomtemperature (25C) and 50C, but it may also be applied at hightemperatures up to 90C, depending on circumstances.

If the application is by immersion, the sheet may then be passed throughsqueeze rollers to adjust the amount of coating. If the application isby immersion at a temperature of about 90C, it is also possible to omitthe entire preheating step. i

The coated sheet then is preferably dried by a hot-air blast.

Table 2 shows the drying time for coating a dry metal sheet with thelubricant of the invention at an amount of 10 g/m and a residualmoisture content of 5%. The lubricant employed in these and other testswas that of Example 1, to be described below. i

TABLE 2 Relationship between drying conditions and drying time temp. ofsheet The lubricant of the invention may be used on any kind of steelsheet or steel of other forms. However, a sheet steel of a thicknessbelow 3.2 mm is preferred. Preferably, the coating of this type of sheetsteel is effected at a conveyor line speed below 100 m/min. The optimumconcentration of the aqueous solution applied 6 is between 25 and 60% byweight. Preferably, the amount applied of the lubricant is about 1 to 30g/m on the dry sheet.

The hot blast for drying is preferably applied at a temperature betweenand 200C and a blast velocity of 2 to 20 m/sec. The residual moistureshould in any case be below 10% and preferably be below 5%.

If the water-soluble synthetic resin used in the lubricant of theinvention contains an amine group, a separate anti-corrosion agent maynot be necessary. Otherwise, it is preferred to add about 0.05 to 5% ofanti-corrosion agent, this amount being relative to the total amount oflubricant.

The following example will further illustrate the invention.

In these examples, as well as in the tables mentioned before, thefollowing materials were employed:

The water-soluble resin in the above tables and in all examples, exceptExample 5, was a linseed oil-modified alkyd resin which was combined(further modified) with a cresol novolac resin. The particularcommercial product is identified as Hitanol 6080N. This is a product ofthe Hitachi Company, Ltd. of Japan. In Example 5 a similar resin wasused, except that the novolac-type resin was a phenol resin. Thisproduct is identified as Hitanol 311 of the same company.

The alkyd resin is the conventional reaction product of a polybasic acidand polyhydric alcohol. In the examples the polybasic acid was phthalicanhydride and the alcohol was glycerol.

Instead of the linseed oil modification a tung oil or castor oilmodification could also be resorted to.

The water-soluble surface-active agent in all above tables and allexamples was beef tallow soda soap. However, in Table 6, included inExample 4, comparisons are shown with other water soluble surface-activeagents which show that similar results can be obtained with othersurface-active materials.

Except where otherwise indicated, the beef tallow soda soap used in theabove tables and the examples is the product commercially availableunder the tradename Dice-Lex and is a product of the Nippon Oil and FatCompany, Ltd. of Japan.

The water-soluble oil used in the above tables and in the examples,except as otherwise indicated, was a mineral base cutting oil which isincorporated in the water by emulsification. Its product identificationis .115 K- 2241 WI. Table 3, which forms part of Example 1, shows theuse of different types of water-soluble oils which, however, all comeunder the above general description of mineral oil base water-soluble orwateremulsifiable cutting oils. Where nothing else is indicated, theproduct employed was the product available under the tradename Griton l14 from the Toho Chemical Industries Company, Ltd. of Japan.

EXAMPLE 1 18.6 parts of beef tallow soda soap as identified above, 18.6parts of a water-soluble phenol-modified linseed-modified alkyd resin,and 6.9 of water-soluble oil were dissolved in 55.9 parts of water at atemperature of 60-80C. The water-soluble phenol alkyd resin had a pH of9.0, a viscosity of 4.10 (poise) and a reddish-brown color. Thewater-soluble oil had a density of 0.93, a contents of non-volatiles of93% and also a reddish-brown color.

The steel sheet was a sheet of 460 mm width (blank diameter) and 0.8 mmthickness. It was first cleansed and degreased. The lubricant was thenapplied and, after application, was subjected to drying for 6 minutes ata temperature of 120C. A well-dried film of high anti-stick propertieswas thus obtained. The sheet itself consisted of cold-rolled steel. Theflat-bottom deepdrawing in the following test was effected with a diepunch of 200 mm diameter SR and an opposed die of 203 mm diameter R.After carrying out the drawing operation on the coated steel sheet, theouter diameter, after breakage, was measured to determine the lubri-:ating property of the deep-drawing operation.

The test results appear from the following Table 3.

TABLE 3 EXAMPLE 2 Outer diameter Surfactant Resin after breakage TestNo. Dice-Lex Hitanol 6080N" Water-soluble oil (mm) Remarks (all tests) 118.6 parts 18.6 parts 6.9 parts 406 coating Griton 113 condition: 2 6.9parts Griton' 1 14" 405 coating 3 6.9 parts on die Griton 120" 409 side;4 6.9 parts Griton 1000" 411 drying 5 6.9 parts Sorton C 409 condition:control: superior stamping oil B (one side) 440 120C, 6 min.

The so-called superior stamping oil B was a commerzial product used forcontrol purposes, which had a vis- :osity of 660.

As can be seen from the test, where the die side of the :heet blank waslubricatedwith this latter oil, the outer iiameter after breakage was440 mm.

As distinguished with the lubricant of the invention "Tests 1-5), theouter diameter after breakage was 105-41 1 mm. The lubricant in thesecases was also apalied to the die side of the steel sheet.

With reference to the drawings, FIG. 1 shows that the inter diameter,after breakage, with a lubricant vherein the beef tallow soda soap andthe water-soluale phenol alkyd resin were present at a ratio of 50:501nd the amount of water-soluble oil was varied as indi- :ated, thedifferent figures for the outer diameter after )reakage were obtained.The low figure with a vater-soluble oil addition is particularlyremarkable.

his table shows the outer diamctels at breakage upon die drawing ofcircular anc steel sheets. The lower the number the better arc theresults obtained. stamping speed 18 m/min of flat-bottom drawing.

iameter after breakage D 360 to 390 mm.

TABLE 5 Comparison of LDR (limit drawing ratio).

steel sheet steel sheet Lubricant SPC 3 SPC 1 according to Ex. 2 2.3752.300 commercial dry lubricant film B 2.300 2.225 Stamping Oil B 2.2252.175 Stamping Oil A 2.000 1.970

Note:

commercial dry lubricant film B (fatty acid salt) Stamping oil A(machine oil viscosity Stamping oil B (machine oil viscosity 660)EXAMPLE 3 16 parts of beef tallow soda soap, 24 parts of watersolublephenol alkyd resin, and 10 parts of water-soluble oil were dissolved inwater as in Example 2. This solution, as in Example 2, was applied onthe die side of cold rolled steel sheet (SPC-3, 480 mm blanked diameterand 0.8 mm thickness). With the same test as in Example 2, the resultswith the lubricant according to the present invention were a diameterafter breakage of D 370-380 mm, while prior-art stamping oil B gave D440 mm to 445 mm, stamping oil A gave D 460 to 465 mm, commercial drylubricant B gave D 435 to 440 mm, and commercial dry lubricant A gave D445 to 455 mm. FIG. 2 shows these values in graph form which indicatethat the present invention is by far supe- TABLE 7 outer diameter riorto the conventional lubricants in fiat bottom deep 5 f l' l-lltachiCompany, Ltd.) 395 drawmg alkyd resin (water 501 TD-125 of NipponReichhold Company) 392 melamine resin series (Isquper b ham TD-95 of i nEXAMPLE 4 Riichhdl t i) ppo 40s 1O rnethoxymethylated nylon of the 30parts of each of the soaps 1n Table 6 were added nylon Series sold byTeikoku to parts of a phenol alkyd resin and 5 parts of a ChemicalCompany, Ltd.) 402 water-soluble oil. Table 4 shows the test results offlat acetate Kagak" KL) 407 bottom deep drawing obtained when theselubricants dissolved in 50 parts of warm water were coated on theEXAMPLE 6 die side of cold rolled steel sheet similar to that in Ex- 15ample 1, followed by drying. Similarly as 1n Example 2, 12.9 parts eachof the water-soluble cutting oils in Table 8 were added to parts of beeftallow soda soap and 20 parts of phenol TABLE 6 alkyd resin. Table 8shows the test results as 1n Example 20 l in which flat bottom deepdrawing was carried out Soaps g i z using the lubricant dissolved in 50parts of warm water.

' 61' 1'5 a e mm semi-hydrogenated beef tallow potash s oal (anionic)360 TABLE 8 Fziiiiizfiid? potash map 405 outer diameter polyoxyethylenelauryl ether Water-soluble oil after breakage (mm) (non-ionic) 380mineral oil emulsion 23332:: 3 5 2533" 405 (trade name Swallow Cut No.4"sorbiton trioleate (non-ionic) 4l0 8" sekyu CO Ltd) 403 lauryl aminoacetate, mineral oil emulsion stearyl amino acetate (cationic) 410 i PmCm g of 405 oleic acid soda soap (anionic) 400 Dalkyo Sek'yu Lt control:stamping oil B 400 EXAMPLE 7 EXAMPLE 5 Table 9 shows the results ofstamping tests of cold The water-soluble synthetic resin identified inTable rolled steel sheet of 0.8 mm thickness coated with the 7 was addedto 25 parts of semi-hydrogenated beef tallubricant of Example 1 whichwas subjected, respeclow soda soap and 7.0 parts of water-soluble oil.Table tively, to hot-blast drying, a preheating process, and 3 shows thetest results of flat bottom deep drawing combined preheating andhot-blast drying.

TABLE 9 coating drying cooling Stamping properties process processprocess: preheating airless hot blast cold-air blast residual height ofplate process spray 5 m/sec. for 5 see after moisture after stretchRemarks coating LDR fonning* none 10 /m 150C 25% 1.88 49.0

5 sec. H 150C 40 see. below 5% 2.39 62.1 'I 300C too many bubbles d d 5sec. 7% 2.25 58.0 on surface egrease liquid C, none after 5 sec. 31%1.90 48.6 1 sec.

10 sec. after 5 sec. 24% 1.86 49.2 hot Water C 100C, 1 sec. 5 sec. 22%1.92 49.3 hot water 100C 150C sec. 10 g/m 5 see. after 5 see. below 5%2.36 62.4 better pressure steam 6 kg/cm 150C 1 sec. 5 sec. below 5% 2.3862.3 best Note: residual moisture (W-W.,)/W the larger the number, thebetter is the result obtained in Example 1 in 50 parts of warm water.

W weight of film/unit area W, perfectly dry weight/unit area Table 10shows the results obtained by coating the above lubricant on hot rolledsteel sheet of 3.2 mm

thickness and preheating to dry it, and otherwise similar conditions.

tests as to the residual moisture therein and the resistance tosticking.

TABLE 10 Stamping properties coating drying cooling height of processprocess process residual stretch Preheating airless hot blast cold drawmoisture forming process spray m/sec. 5 m/sec. LDR (mm) Remarks none g/m150C 5 sec. 29% 1.73 r 49.7

I, I, I

5 sec. 17% 1.82 50.5

5 sec. 1.74 50.1 too many bubbles on the surface degreased liquid 100Cnone after 31% 1.72 50.0 1 sec. 5 sec. degreased liquid 100C 10 sec. 26%1.70 49.8

hot water 100C 150C l sec. 5 sec. 21% 1.75 50.3 hot water 100C 10 sec.9% 1.88 64.0

hot water 7 100C below 40 sec. 5% 2.03 68.2 good drawing results.

but excessive time required highpressure steam 6kg/cm 2.02 68.4 1 sec.

In connection with Table 9 and Table 10, the values TABLE 12 of LDR wereobtained under the following conditions: Residual punch diameter: 200mm, radius of die shoulder: 5 mm, Exmoisture punching speed: 18 m/min.The height of stretch formggz 3 7 I5 30 ing was obtained under thefollowing conditions: spherical punch of radius 75 mm, die: 160 mm 1ndiameter, 40

relative O X bead: 190 mm in diameter and punch speed. 100 humiditymm/min. 3 hours 35C 7: relative According to the method of the presentinvention, as iumidity O O X x is evident from Table 9 and Table 10, theresidual mo1s- 45 30 days TABLE 1 1 Exposure time Residual moisture (72)45 days 0% 1% 8% 12% 90 days 16% 20% 21% Note: cold rolled steel sheetwas used.

Test conditions:

temperature: 18 30C relative humidity: 40 83% coating amount: 10 g/m"Table 12 shows the results of similarly performed excellent 0 medium 7 Xpoor coating amount: 10 g/m load: 2 kg/cm As shown in Table 11 and Table12, it is advantageous to reduce the residual moisture below 5%, bothfrom the test results on rusting and the resistance to sticking.Furthermore, even if the lubricant of the present invention is coated onsteel sheet with water-soluble skin pass oil, there is only littleeffect obtained. That is to say, when the lubricant of this inventionwas coated in an amount of 10 g/m on cleansed steel sheet by the methodof the invention, the LDR was 2.39. When the steel sheet was coated withthe commercial product Multi-luble 50 A (trade name) in an amount of 0.2g/m the limit of the drawing ratio was 2.36.

EXAMPLE 8 Table 1 3 shows comparative, tests of cold drawing propertiesobtained in following two methods: 50 parts of water were added to themixture of 23 parts of Dice- Lex which is beef tallow soda soap and 27parts of Hitanol 6080 N (water-soluble phenol alkyd resin). The mixturewas heated to-C and coated on carbon steel tube STKM44 (42.7 mm in outerdiameter and 4.5 mm

Appreciating standards:

in thickness). The tube was drawn to a reduction in 13 area of 20%, 30%and 40%, respectively, and the drawing loads were measured. As control,values were obtained by using zinc phosphate and fatty acid soap. Thepresent invention got nearly equal results with those of theabove-mentioned lubricants which were obtained in substantially morecomplicated processes.

7.0 parts of water-soluble oil were mixed with 21.5 parts of beef tallowsoda soap and 21.5 parts of water soluble phenol alkyd resin. 50 partsof water at 20C were then added. The solution formed was heated to 70C,and the same steel tube as in Example 8 was drawn to reduction in areaof 20%, 30% and 40%, and the drawing loads were measured. As describedin Example 8, the values thus obtained were compared with those obtainedby using zinc phosphate and fatty acid soap lubricant. Table 14 showsthe comparison tests.

TABLE 14 Ratios of reduction in area 20% 30% 40% method of the invention10.4 t 13.0 t 15.0 t lubricant: zinc phosphate and fatty acid soap 10.5t 12.3 t 15.2 t

As can be seen, with addition of water-soluble oil, results superior tothose of conventional methods were obtained. The lubricant of theinvention does not require the conventional zinc phosphate treatment(80C), water-washing thereafter, neutralizing treatment (80C) and fattyacid soap treatment (75C). That is, the lubricant of the invention istreated at 2040C and this step of treatment therefore is very simple.After drawing even if being left for 1 month, no corrosion is noted, andif washed in alkali after drawing, metallic glaze remained on thesurface. Roughness of surface was less than 1 micron in H max.

EXAMPLE TABLE 15 Ratios of reduction in area method of the invention14.1 t 17.7 t

TABLE l5-continued Ratios of reduction in area lubricant:

zinc phosphate and fatty acid soap 13.5 t 15.9 t

EXAMPLE 1 l 7.0 parts of water-soluble oil were added to 21.5 parts ofbeef tallow soda soap and 21.5 parts of watersoluble phenol alkyd resin.Thereto 50 parts of water were adde as described in each of theexamples. The same steel tube as described in Example 1 1 was coated andthen drawn to reduction in area of 20% and 30%. The measured drawingload was compared with those necessary with conventional methods asstated above. The results appear from Table 16.

TABLE 16 ratios of reduction in area 20% 30% method of the invention12.7 t 15.4 t lubricant: zinc phosphate and fatty acid soap 13.5 t 15.9t

This case confirms the superiority to the conventional method. The sameexcellent results were also obtained in Examples 11 and 12 as inExamples 9 and 10.

EXAMPLE 12 7.0 parts of water-soluble oil were added to 21.5 parts ofbeef tallow soda soap and 21.5 parts of watersoluble phenol alkyd resin.Thereto 50 parts of water were added. The lubricant was used for coatingmild steel wire, electric copper wire and electric aluminum wire, eachbeing 1.54 mm in diameter, and each then drawn to a reduction in area of20%. The drawing load was compared with those necessary with theconventional lubricant, as shown in Table 17.

18.6 parts of beef tallow soda soap and 18.6 parts of water-solublephenol alkyd resin were added to 60 parts of hot water at temperaturesof 6080C under the same condition as in Example 1 (Griton 114). Flatbottom drawing test with the lubricant was 425 mm in the outer diameterafter breakage.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and 16 soda soap,polyoxyethylene lauryl ether, polyoxyethylene sorbitan monooleate,sorbitan trioleate, lauryl amino acetate, and stearyl amino acetate anda watersoluble synthetic resin which is a combination of an oilmodifiedalkyd resin with a phenol or cresol-novolactype resin, the twocomponents being present in relative amounts between 20 and of the saidsurfaceactive agent and between 80 and 20% of the said synthetic resin.

1. A DRY LUBRICANT FOR COATING STEEL TO PREPARE IT FOR DEEP DRAWING ANDMOLDING OPERATIONS, THE LUBRICANT COMPRISING A MIXTURE OF SURFACE-ACTIVEAGENT SELECTED FROM THE GROUP CONSISTING OF SEMI-HYDROGENATED BEEFTALLOW POSTASH SOAP, OLEIC ACID POSTASH SOAP, OLEIC ACID SODA SOAP,POLYOXYETHYLENE LAURYL EITHER, POLYOXYTHYLENE SORBITAN MONOOLEATE,SORBITAN TRIOLEATE, LAURYL AMINO ACETATE, AND STEARYL AMINO ACETATE ANDA WATER-SOLUBLE SYNTHETIC RESIN WHICH IS COMBINATION OF AN OIL-MODIFIEDALKYD RESIN WITH A PHENOL OR CRESOL-NOVOLAC-TYPE RESIN, THE TWOCOMPONENTS BEING PRESENT IN RELATIVE AMOUNTS BETWEEN 20 AND 80% OF THESAID SURFACE-ACTIVE AGENT AND BETWEEN 80 AND 20% OF THE SAID SYNTHETICRESIN.